The 1952 Pentagon Press Conference

The radar operators who actually watched the screens believed they were tracking real, solid objects. The CAA controllers at National Airport said the same thing to one another in real time and to investigators after the fact. Lt. Holcomb, the Navy radar specialist who had been brought in specifically to evaluate the returns, told Major Fournet during the second-weekend incident that what he was watching could not be a temperature inversion. The blips were too defined, the speeds too consistent, the manoeuvres too purposeful. Holcomb's assessment did not appear in the press briefing.

The F-94 interceptor pilots who pursued the contacts on the second weekend reported visual confirmation of fast-moving lights that paced their aircraft and accelerated away on demand. Capt. William Patterson chased one cluster of lights at full throttle and reported being surrounded by them at one point before they disappeared. His debrief was conducted by the Air Force but was not made public in 1952. The pilots' visual reports were not cited at the briefing.

The temperature-inversion hypothesis had a problem. Inversion layers had been present over Washington on many nights that summer. Radar artefacts from inversions had appeared on the screens many times. The controllers and the technical staff could distinguish inversion blips from solid targets. The Washington returns of 19-20 July and 26-27 July did not behave like inversion artefacts. They behaved like aircraft. This empirical distinction, well known inside the radar community, did not feature in Samford's account to the press.

The 29 July briefing achieved its surface objective. The Washington Post, the New York Times, and the wire services reported the temperature-inversion explanation as the Air Force's authoritative finding. Public interest in the Washington flap subsided within days. But inside the Air Force, the file did not close. Project Blue Book's own statistical analysis of the year produced an "unexplained" rate of over 20 percent for 1952, the highest in the programme's history. Ruppelt himself, who had stood next to Samford at the podium, would write four years later that the Washington case was one of those that did not fit the standard explanations.

The summer of 1952 was the peak of the first sustained American UFO wave. Project Blue Book recorded over 1,500 UFO reports that calendar year, more than any year before or since. The Washington contacts were the high-water mark, but they were not isolated. In late June the Air Force tracked a UFO over Greenham Common in England; on 13 July a Pan American flight crew reported eight discs over Norfolk, Virginia; on 23 July four Air Force pilots near Salisbury, North Carolina, chased multiple lights for half an hour. The Washington events arrived into a national news environment already primed for the next sighting.

The political pressure on the Air Force escalated rapidly. President Truman asked his Air Force aide, Robert Landry, for an explanation within hours of the first weekend of contacts. CIA Director Walter Bedell Smith briefed the National Security Council in early August. The Robertson Panel, convened in January 1953 in direct response to the 1952 wave, would recommend that the Air Force conduct a public-relations campaign to "debunk" UFO reports and reduce public interest. That recommendation shaped Project Blue Book's public posture for the rest of its existence.

Samford's 50-percent figure for explained cases was generous. Blue Book's internal statistics for 1952 listed approximately 22 percent of reports as "unknown" even after investigation. Among those unknowns were the Washington contacts. They remained classified as unknown in the Blue Book files until the programme ended in 1969. The temperature-inversion explanation, presented to the press as the Air Force's settled finding, was never officially adopted as Blue Book's case disposition for the Washington events themselves.